AM29BDD160G datasheet(39/80 Pages) AMD

39 / 80 page

Am29BDD160G

Automatic sector erase operations begin on the ris-

ing edge of the WE# or CE# pulse of the last sector

erase command issued, and once the 80 µs time-out

window has expired. The status of the sector erase

operation is determined three ways:

■

Data# polling of the DQ7 pin

■

Checking the status of the toggle bit DQ6

■

Checking the status of the RY/BY# pin

Further status of device activity during the sector

erase operation is determined using toggle bit DQ2

(refer to DQ2: Toggle Bit II).

When the Embedded Erase algorithm is complete,

the device returns to reading array data, and ad-

dresses are no longer latched. Note that an address

change is required to begin read valid array data.

Figure 5 illustrates the Embedded™ Erase Algorithm,

using a typical command sequence and bus opera-

tion. Refer to the Erase/Program Operations tables in

the AC Characteristics section for parameters, and to

Figure 22 for timing diagrams.

Note:

1. See Tables 18 and 20 for erase command sequence.

2. See DQ3: Sector Erase Timer for more information.

Figure 5. Erase Operation

Sector Erase and Program Suspend

Command

The Sector Erase and Program Suspend command

allows the user to interrupt a Sector Erase or Pro-

gram operation and perform data read or programs

in a sector that is not being erased or to the sector

where a programming operation was initiated. This

command is applicable only during the Sector Erase

and Programming operation, which includes the

time-out period for Sector Erase.

Sector Erase and Program Suspend

Operation Mechanics

■

A successful erase pulse has a duration or 1.2 ms

± 20%, depending on the number of previous

erase cycles (among other factors).

■

A successful sector erase operation requires 300

successful erase pulses.

■

An internal counter monitors the number of erase

pulses initiated and has a maximum value of

5980.

The counter is incremented by one every time an

erase pulse is initiated, regardless of whether or not

that erase pulse is successful. An erase pulse is ter-

minated immediately when the suspend command is

executed. A new erase pulse is initiated when the re-

sume command is executed (and the counter is

incremented).

Given that 300 successful erase pulses are required,

a successful sector erase operation shall have a

maximum of 5680 erase suspends.

The Sector Erase and Program Suspend command is

ignored if written during the execution of the Chip

Erase operation or Embedded Program Algorithm

(but will reset the chip if written improperly during

the command sequences). Writing the Sector Erase

and Program command during the Sector Erase

time-out results in immediate termination of the

time-out period and suspension of the erase opera-

tion. Once in Erase Suspend, the device is available

for reading (note that in the Erase Suspend mode,

the Reset command is not required for read opera-

tions and is ignored) or program operations in

sectors not being erased. Any other command writ-

ten during the Erase Suspend mode is ignored,

except for the Sector Erase and Program Resume

command. Writing the Erase and Program Resume

command resumes the sector erase operation. The

bank address of the erase suspended bank is re-

quired when writing this command

If the Sector Erase and Program Suspend command

is written during a programming operation, the de-

vice suspends programming operations and allows

only read operations in sectors not selected for pro-

gramming. Further nesting of either erase or

programming operations is not permitted. Table 18

summarizes permissible operations during Erase and

Program Suspend. (A busy sector is one that is se-

lected for programming or erasure.):

Embedded

Erase

algorithm in

progress

Table 18. Allowed Operations During

Erase/Program Suspend

Sector

Program Suspend

Erase Suspend

Busy Sector

Program Resume

Erase Resume

Non-busy

sectors

Read Only

Read or Program

AM29BDD160G датащи(PDF) 39 Page - Advanced Micro Devices

AM29BDD160G датащи(HTML) 39 Page - Advanced Micro Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80

датащи скачать

ссылки URL